From 449f72ed034134bb7ea2ed5b356df8eee887f5a7 Mon Sep 17 00:00:00 2001
From: Sam Perry <u1265119@unimail.hud.ac.uk>
Date: Sat, 1 Oct 2016 11:23:07 +0100
Subject: [PATCH] Completed step 1

Created plot showing linearity of FSR over increasing pressure.
Added live plotting python script.
---
 .gitignore           |   5 +-
 src/ArduinoPyPlot.py | 112 +++++++++++++++++++++++++++++++++++++++++++
 src/sketch.ino       |  21 ++++++++
 3 files changed, 137 insertions(+), 1 deletion(-)
 create mode 100644 src/ArduinoPyPlot.py

diff --git a/.gitignore b/.gitignore
index 021b2a4..17e7bb8 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,5 @@
-.build
+.DS_Store
+bin/*/
+*build*
+*~
 
diff --git a/src/ArduinoPyPlot.py b/src/ArduinoPyPlot.py
new file mode 100644
index 0000000..4614e61
--- /dev/null
+++ b/src/ArduinoPyPlot.py
@@ -0,0 +1,112 @@
+"""
+ldr.py
+Display analog data from Arduino using Python (matplotlib)
+Author: Mahesh Venkitachalam
+Website: electronut.in
+"""
+
+import sys, serial, argparse
+import numpy as np
+from time import sleep
+from collections import deque
+
+import matplotlib.pyplot as plt
+import matplotlib.animation as animation
+
+
+# plot class
+class AnalogPlot:
+  # constr
+  def __init__(self, strPort, maxLen):
+      # open serial port
+      self.ser = serial.Serial(strPort, 9600)
+
+      self.ax = deque([0.0]*maxLen)
+      self.ay = deque([0.0]*maxLen)
+      self.maxLen = maxLen
+
+  # add to buffer
+  def addToBuf(self, buf, val):
+      if len(buf) < self.maxLen:
+          buf.append(val)
+      else:
+          buf.pop()
+          buf.appendleft(val)
+
+  # add data
+  def add(self, data):
+      assert(len(data) == 2)
+      self.addToBuf(self.ax, data[0])
+      self.addToBuf(self.ay, data[1])
+
+  # update plot
+  def update(self, frameNum, a0, a1):
+      try:
+          line = self.ser.readline()
+          data = [float(val) for val in line.split()]
+          # print data
+          if(len(data) == 2 and not pause):
+              self.add(data)
+              a0.set_data(range(self.maxLen), self.ax)
+              a1.set_data(range(self.maxLen), 0)
+      except KeyboardInterrupt:
+          print('exiting')
+
+      if not pause:
+        return a0,
+
+  # clean up
+  def close(self):
+      # close serial
+      self.ser.flush()
+      self.ser.close()
+
+pause = False
+def onClick(event):
+    global pause
+    pause = not pause
+
+# main() function
+def main():
+  # create parser
+  parser = argparse.ArgumentParser(description="LDR serial")
+  # add expected arguments
+  parser.add_argument('--port', dest='port', required=True)
+
+  # parse args
+  args = parser.parse_args()
+
+  #strPort = '/dev/tty.usbserial-A7006Yqh'
+  strPort = args.port
+
+  print('reading from serial port %s...' % strPort)
+
+  # plot parameters
+  analogPlot = AnalogPlot(strPort, 300)
+
+  print('plotting data...')
+
+  # set up animation
+  fig = plt.figure()
+
+  ax = plt.axes(xlim=(0, 300), ylim=(0, 1023))
+  a0, = ax.plot([], [])
+  a1, = ax.plot([], [])
+  fig.canvas.mpl_connect('button_press_event', onClick)
+  anim = animation.FuncAnimation(fig, analogPlot.update,
+                                 fargs=(a0, a1),
+                                 frames=None,
+                                 interval=50)
+
+  # show plot
+  plt.show()
+
+  # clean up
+  analogPlot.close()
+
+  print('exiting.')
+
+
+# call main
+if __name__ == '__main__':
+  main()
diff --git a/src/sketch.ino b/src/sketch.ino
index 9f91418..1acd60f 100644
--- a/src/sketch.ino
+++ b/src/sketch.ino
@@ -1,8 +1,29 @@
 
+// analog-plot
+// 
+// Read analog values from A0 and A1 and print them to serial port.
+//
+// electronut.in
+
+#include "Arduino.h"
+
 void setup()
 {
+  // initialize serial comms
+  Serial.begin(9600); 
 }
 
 void loop()
 {
+  // read A0
+  int val1 = analogRead(0);
+  // read A1
+  int val2 = analogRead(1);
+  // print to serial
+  Serial.print(val1);
+  Serial.print(" ");
+  Serial.print(val2);
+  Serial.print("\n");
+  // wait 
+  delay(50);
 }